1. Field of Invention
The present invention relates to a thin film transistor, a method of producing the same, an electrooptic apparatus, and a sensor.
2. Description of the Related Art
Since the report made by the group led by Professor Hideo Hosono (Frontier Research Center & Materials and Structures Laboratory of the Tokyo Institute of Technology) and other researchers, there has been an increase in studies of the application of In—Ga—Zn—O oxide materials (also which may be referred to as “IGZO” or “IGZO materials” hereinafter) to active layers of thin film transistors (TFTs) (see, for example, Science, 300 (2003) 1269, Nature, 432 (2004) 488).
The IGZO materials exhibit higher carrier mobility than that of amorphous silicon (a-Si). In addition, IGZO materials can be formed into films on resin substrates at low temperatures. For these reasons, it is expected that IGZO materials will be applied to, for example, driving elements of flexible displays or the like in the future.
As an example of a TFT prepared using an IGZO material, a TFT is disclosed in which an active layer, as well as a high-resistance layer that is arranged between the active layer and a gate insulating film, are formed from IGZO material, thereby attaining excellent TFT properties (see, for example, Japanese Patent Application Laid-Open (JP-A) No. 2007-73701).